[tex]\begin{gathered} the\text{ final answer is } \\ (x-3)^2=128 \end{gathered}[/tex]
[tex]\begin{gathered} 3x^2-18x=357 \\ divide\text{ through by 3} \\ \\ x^2-6x=119 \end{gathered}[/tex]
to complete the square , use , [ half X coefficient of x ]^2
[tex]\begin{gathered} \frac{1}{2}\times-6=-3 \\ \\ (x-3)^2=x^2-6x+9 \\ (x-3)^2-9=x^2-6x \end{gathered}[/tex]
replece x^2-6x with (x-3)^2 - 9
[tex]\begin{gathered} (x-3)^2-9=119 \\ (x-3)^2=119+9 \\ (x-3)^2=128 \end{gathered}[/tex]
